JP2004232292A

JP2004232292A - Brace damper

Info

Publication number: JP2004232292A
Application number: JP2003020850A
Authority: JP
Inventors: Kazuhiko Isoda; 和彦磯田
Original assignee: Shimizu Construction Co Ltd; Shimizu Corp
Current assignee: Shimizu Construction Co Ltd; Shimizu Corp
Priority date: 2003-01-29
Filing date: 2003-01-29
Publication date: 2004-08-19

Abstract

<P>PROBLEM TO BE SOLVED: To provide a brace damper capable of being miniaturized with a lightweight design and preventing fracture resulting from stress concentration. <P>SOLUTION: A restrained member 12 for restraining buckling while allowing axial deformation is put on the outside of a core material 11 composed of a band steel plate. The core material is formed as an yielding part 11a constant in width all over the whole length except for both ends of the core material, and only the both ends are formed as fixed parts 11b expanded in widths wider than that of the yielding part. A reinforced member such as a reinforced rib 13 or the like used for a mounting member to a building and enhancing the out-of-plane rigidity of the fixed section is provided to the fixed section. The restrained member comprises a pair of out-of-plane stiffeners such as a channel steel 14 or the like for restraining those out-of-plane bucklings by sitting astride the fixed part from the yielding part of the core material and a pair of in-plane stiffeners such as a band steel 15 or the like for restraining the in-plane buckling of the yielding part of the core material. The channel steel as the out-of-plane stiffeners and the band steel as the in-plane stiffeners are assembled in an H-shape. The reinforced rib 13 or the reinforced member such as a flange steel plate or the like is mounted to the fixed part to form a cross-shaped or an H-shaped section in both ends of the core material by mounting the reinforced rib 13 or the reinforced member such as the flange steel plate or the like to the fixed part. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、建物にブレースとして設置されるとともに建物の振動エネルギーを吸収するダンパーとしても機能するブレースダンパーに関する。
【０００２】
【従来の技術】
建物の要所に制震ダンパーを設置して地震による振動や損傷をコントロールする制震構造が一般化しつつある。この種の構造に適用する制震ダンパーとしては鋼材ダンパー、摩擦ダンパー、粘性系ダンパー等、各種のものがあるが、特に鋼材の降伏に伴う履歴吸収エネルギーを利用する鋼材ダンパーはローコストで大きな減衰性能を発揮できるものであることから広く採用される気運にあり、なかでもブレースタイプの鋼材ダンパーは機構が簡単で設計的にも扱い易く、設置スペースもさして必要としないことから、最も有効と考えられている。
【０００３】
この種のブレースタイプの鋼材ダンパーとして、たとえば特許文献１あるいは非特許文献１や非特許文献２に示されるように、軸方向に降伏する帯鋼板を芯材としてその座屈を外側から拘束する構造のものが提案されている。
【０００４】
【特許文献１】
特開２００２−２３５３８０号公報
【非特許文献１】
小林、外２名、「座屈拘束ブレースの軽量化に伴う耐力確認実験」、
日本建築学会大会学術講演梗概集（北陸）、２００２年８月、ｐ．５４９〜５５０
【非特許文献２】
中村、外５名、「実大アンボンドブレースの疲労性能（その２：実験結果）」、日本建築学会大会学術講演梗概集（中国）、１９９９年９月、ｐ．８１５〜８１６
【０００５】
特許文献１に示されるブレースダンパーは、図９に示すように、両端部が建物に対して固定されてブレースとして機能する芯材１の外側に拘束部材２を装着して芯材１の座屈を拘束するようにしたものであり、芯材１の中央部における幅寸法を小さくすることでそこを降伏部１ａとして設定し、その降伏部１ａに塑性歪を集中させて降伏させる構造のものである。
【０００６】
非特許文献１に示される座屈拘束ブレースは、図１０に示すように芯材３の外側に溝形鋼や帯鋼等からなる拘束部材４を装着して座屈を拘束するようにしたものであるが、芯材３には降伏部を格別に設けることなくその幅寸法を一定としたストレートタイプのものである。このようなストレートタイプのものでは、降伏部を設ける場合に較べて塑性歪が芯材３の全長に分散されて小さくなるので、エネルギー吸収効率はややや低下するものの疲労特性は優れるものである。非特許文献２に示されるアンボンドブレースダンパーも、図１１に示すように芯材３の両端部の幅寸法をやや大きくしてはいるが上記と同様のストレートタイプのものである。
【０００７】
【発明が解決しようとする課題】
ところで、特許文献１に示されるブレースダンパーは、芯材１の中央部に降伏部１ａを設けていることから、その降伏部１ａに塑性歪が集中して効果的に地震エネルギーを吸収できるものではあるが、その反面、降伏部１ａ以外の幅寸法をダンパーとしての必要最小限の寸法よりも大きくせざるを得ないので、全体の小形軽量化を図る上ではやや難があった。
【０００８】
一方、非特許文献１および非特許文献２に示されるストレートタイプのものでは、その幅寸法を必要最小限とすることが可能であって小形軽量化を図る上では有利であるが、その反面、芯材３の全長にわたって塑性歪が分散されることから、拘束部材４により座屈が拘束される部分と拘束されない部分との境界部に応力が集中し、特に芯材３の両端部に設ける補強リブ５の先端の位置５ａを起点として芯材３に破断が生じ易いという問題があった。
【０００９】
上記事情に鑑み、本発明は、充分に小形軽量化を図ることができ、かつ局所的な破断が生じるようなことも防止できる有効なブレースダンパーを提供することを目的とする。
【００１０】
【課題を解決するための手段】
請求項１の発明は、建物にブレースとして設置されるとともに建物の振動エネルギーを吸収するダンパーとしても機能するブレースダンパーであって、両端部が建物に対して固定されて所定軸力を受けた際に降伏する帯鋼板からなる芯材と、芯材の外側に装着されてその軸方向変形を許容しつつ座屈を拘束する拘束部材とを有し、芯材は、両端部を除いてほぼ全長にわたり幅寸法が一定の降伏部とされるとともに、両端部のみは降伏部よりも幅寸法が大きくされた固定部とされて、その固定部には建物への取付部材を兼ねるとともに固定部の面外剛性を高めるための補強部材が設けられ、拘束部材は、芯材の降伏部から固定部に跨ってそれらを両面側から挟み込むことでそれら降伏部および固定部の板厚方向への面外座屈を拘束する対の面外補剛材と、芯材の降伏部の両側において双方の面外補剛材に対して締結されてそれら面外補剛材どうしを連結するとともに降伏部の板幅方向への面内座屈を拘束する対の面内補剛材からなることを特徴とする。
【００１１】
請求項２の発明は、請求項１の発明のブレースダンパーにおいて、面外補剛材は芯材を挟み込むウエブとその両側縁部に一体に形成されたフランジを有する溝形鋼からなり、面内補剛材は双方の面外補剛材のフランジに対して締結される対の帯鋼からなり、それら溝形鋼と帯鋼とが組み立てられることで拘束部材の断面形状はＨ形とされていることを特徴とする。
【００１２】
請求項３の発明は、請求項１または２の発明のブレースダンパーにおいて、固定部に補強部材が取り付けられることで芯材の両端部における断面形状は十字形あるいはＨ形とされていることを特徴とする。
【００１３】
【発明の実施の形態】
図１〜図４は本発明のブレースダンパーの第１実施形態を示すものである。これは、基本的には図９に示した従来のブレースダンパーと同様に、両端部が建物に対して固定されて所定軸力を受けた際に降伏する帯鋼板からなる芯材１１と、芯材１１の外側に装着されてその軸方向変形を許容しつつ座屈を拘束する拘束部材１２とからなるものであるが、従来のものとは芯材および拘束部材の構成が異なるものとされている。
【００１４】
すなわち、本実施形態のブレースダンパーにおける芯材１１としては、低降伏点鋼あるいは軟鋼からなる帯鋼板が採用され、図４（ａ）に示すようにその両端部を除くほぼ全長にわたる部分が幅寸法が一定とされた降伏部１１ａとされている。そして、建物に対して固定される両端部のみは降伏部１１ａよりも幅寸法が１．５倍程度に大きくされた固定部１１ｂとされ、それら降伏部１１ａと固定部１１ｂの境界部においては幅寸法が滑らかに変化するように円弧部１１ｃが形成されている。また、固定部１１ｂの両面には、芯材１１を建物に対して固定するための取付部材を兼ねるとともに固定部１１ｂの面外剛性を高めるための補強リブ（補強部材）１３が溶接により取り付けられ、それにより図２（ｂ）に示すように芯材１１の両端部の断面形状は十字形をなすものとされている。
【００１５】
また、本実施形態のブレースダンパーにおける拘束部材１２は、芯材１１の板厚方向への面外座屈を拘束する面外補剛材としての対の溝形鋼１４と、板幅方向への面内座屈を拘束する面内補剛材としての対の帯鋼１５からなる。図２（ａ）に示すように、面外補剛材としての溝形鋼１４は、芯材１１の降伏部１１ａにおける幅寸法よりも若干大きい幅寸法のウエブ１４ａと、その両側縁部に一体に形成されたフランジ１４ｂを有するものであり、面内補剛材としての帯鋼１５は背中合わせとされた双方の溝形鋼１４のフランジ１４ｂに対して多数のボルト１６により締結されるものであり、それら溝形鋼１４と帯鋼１５とを芯材１１を取り囲むように組み立てることで拘束部材１２の断面形状はＨ形をなすものとされている。
【００１６】
そして、図３に示すように溝形鋼１４の長さは芯材１１の降伏部１１ａの長さよりもやや長くされていて、この溝形鋼１４は芯材１１の降伏部１１ａから固定部１１ｂに跨るように設けられて、降伏部１１ａのみならずその両端部により固定部１１ｂも同時に挟み込むものとされている。また、帯鋼１５の長さは芯材１１の固定部１１ｂとの干渉を避けるために溝形鋼１４よりも短くされており、その帯鋼１５は降伏部１１ａのみを上下から挟み込む状態で溝形鋼１４に対して締結されている。
【００１７】
上記のように、溝形鋼１４と帯鋼１５とがＨ形に組み立てられて芯材１１に装着された拘束部材１２は、芯材１１の面外座屈および面内座屈を拘束するものであるが、芯材１１をダンパーとして機能させるためには芯材１１の軸方向の変形は拘束しないものとする必要があり、そのため、各溝形鋼１４のウエブ１４ａと芯材１１の表面との間にはそれらをアンボンド（非付着）状態に維持して軸方向の相対変形を許容せしめるための絶縁材１７が介装されている。絶縁材１７としてはたとえばクロロプレンゴム等の高分子系材料からなる１ｍｍ程度の厚さのシート材が好適に採用可能であり、それを図４（ｂ）に示すように溝形鋼１４のウエブ１４ａと同一形状に加工しておいて、拘束部材１２を組み立てる際に予め溝形鋼１４のウエブ１４ａに貼り付けるようにすれば良い。また、芯材１１の降伏部１１ａの両端部における小口面には、帯鋼１５の端部内面との間に介装されるように、同様の絶縁材１８（図４（ａ）参照）を設けておくと良い。
【００１８】
なお、図４（ｃ）に示すように、溝形鋼１４にはこの溝形鋼１４自体の面外剛性を充分に高めるための補剛部材としての縦リブ１９および横リブ２０が溶接され、この溝形鋼１４による芯材１１に対する面外補剛効果が充分に確保されるようになっている。また、溝形鋼１４および絶縁材１７の両端部には、芯材１１の両端部に溶接されている補強リブ１３との干渉を避けるためのスリット２１が形成されている。さらに、溝形鋼１４の両端部は、芯材１１の固定部１１ｂに対してそれらを貫通する綴りボルト２２により連結されているが、綴りボルト２２が芯材１１の軸方向変形を拘束しないように、図４（ａ），（ｂ）に示すように、綴りボルト２２を通すためのボルト孔２３のうち、芯材１１の一端側において固定部１１ｂおよび絶縁材１７に形成されているものは芯材１１の軸方向に長い長穴とされ、かつ綴りボルト２２による締結は本締めすることなく手締めに留めるものとしている。
【００１９】
上記構成のもとに本実施形態のブレースダンパーは、図９に示した従来のブレースダンパーに比較して小形軽量化を図ることができ、かつ図１０〜図１１に示したような従来のストレートタイプのものに比較して局所的な応力集中やそれに起因する破断が生じ難いものであり、両者の利点を併せ持つ極めて有効なものである。
【００２０】
すなわち、図９に示した従来のブレースダンパーは、芯材１の中央部にのみ降伏部１ａを形成して他の部分の幅寸法を降伏部１ａよりも大きくしていることから、全体の小形軽量化を図ることには限界があったが、本実施形態では両端部の固定部１１ｂを除いて芯材１１のほぼ全体を降伏部１１ａとして実質的にその全長にわたって必要最小限の幅寸法とすることができる。
【００２１】
また、芯材１１のみならず拘束部材１２における面外補剛材としての溝形鋼１４も必要最小限の寸法とできるし、溝形鋼１４の成が小さくなることでそのウエブ１４ａの面外変形が小さくなるので、溝形鋼１４による芯材１１に対する面外座屈拘束効果を自ずと向上させることができ、場合によっては溝形鋼１４に設ける補剛部材としての縦リブ１９や横リブ２０を省略ないし軽減することも可能である。さらに、従来のブレースダンパーにおいては降伏部１ａの幅寸法を小さくしていることから、拘束部材２それ自体では降伏部１ａの幅方向への面内座屈を有効に拘束することができず、降伏部１ａが長い場合にはそれらの間に何らかの補剛部材を設ける必要があったが、本実施形態のブレースダンパーでは面内補剛材としての帯鋼１５がそれ自体で芯材１１の全長にわたって面内座屈を確実に拘束することができるから、他に格別の補剛部材を設けるような必要はない。以上のことから、本実施形態のブレースダンパーは、図９に示したような従来のブレースダンパーに比較して充分に小形軽量化を図ることができし、構成の簡略化、単純化を図ることもでき、ローコスト化も実現することができる。
【００２２】
ただし、芯材１１の幅寸法を単に一定にして、その降伏部１１ａに対してのみ単に拘束部材１２を装着することでは、図１０〜図１１に示した従来のストレートタイプのものと同様に、拘束部材１２による拘束部分と非拘束部分との境界部において応力集中が生じ、それに起因して芯材１１の端部での破断が懸念される。そこで、本実施形態では、芯材１１の降伏部１１ａと固定部１１ｂとの境界部に円弧部１１ｃを設けてそこでの断面変化を滑らかにするとともに、拘束部材１２を構成している面外補剛材としての溝形鋼１４を降伏部１１ａから固定部１１ｂに跨るように装着し、かつ芯材１１の固定部１１ｂに設ける補強リブ１３を固定部１１ｂにのみ設けるに留めて降伏部１１ａまで達しないようにし、それにより降伏部１１ａと固定部１１ｂとの境界部に応力集中が生じることを回避してそこでの破断が生じるようなことを防止できるものとなっている。
【００２３】
勿論、本実施形態のブレースダンパーは、汎用の建設資材である帯鋼板や溝形鋼をほぼそのまま採用可能であり、芯材１１の固定部１１ｂに補強リブ１３を溶接し、必要に応じて溝形鋼１４に面外補剛材としての縦リブ１９や横リブ２０を溶接する以外は、単なるボルト締結で容易にかつ安価に組み立てることができるし、その外観は実質的にＨ形鋼と同様のものであるので、通常のブレースや従来のブレースダンパーと同様に格別のスペースを要することなく建物に設置することができる。
【００２４】
なお、上記第１実施形態では芯材１１の両端部の固定部１１ｂに対しその両面側に補強リブ１３を１枚ずつ溶接することで、そこでの断面形状をシンプルな十字形としたが、建物との取り合いの状況等によっては、芯材１１の端部の断面形状を十字形とすることに代えて他の形状、たとえばＨ形とすることも可能である。
【００２５】
図５〜図８は上記第１実施形態を基本として芯材１１の端部の断面形状をＨ形に変更した場合の第２実施形態を示すものである。これは、芯材１１の固定部１１ｂの小口面に補強部材として２枚のフランジ板２４を溶接してそこでの断面形状をＨ形とし、それに伴い、上記第１実施形態においては溝形鋼１４に形成していたスリット２１を省略し、綴りボルト２２の本数を各端部に１本ずつとした点で第１実施形態とは異なるものであるが、その他の構成は第１実施形態と同様のものである。本第２実施形態のブレースダンパーは、基本的に第１実施形態のものと同様の効果が得られることに加え、芯材１１の端部をＨ形とすることで、Ｈ形鋼が多用される建物の柱梁接合部に対する接合がより容易となるし、フランジ板２４により１か所あたりの締結ボルトの本数を確保できるので固定部１１ｂの長さや幅を小さくでき、ボルト列数を削減できるという利点がある。いずれにしても、芯材１１の端部の断面形状は建物との接合部の構造や形態その他の諸条件に応じて最適に設定すれば良く、たとえば一端側を十字形とし他端側をＨ形とするというように両端部を異なる形状とすることも可能であるし、十字形やＨ形以外の形状とすることも勿論可能である。
【００２６】
【発明の効果】
請求項１の発明は、芯材の幅寸法を両端部を除いてほぼ全長にわたり一定としたので、芯材および拘束部材を必要最小限の寸法とすることが可能であって、従来のこの種のブレースダンパーに比較して充分な小形軽量化とローコスト化を図ることができる。また、芯材の両端部のみは幅寸法を大きくしてそこに補強部材を設け、かつ降伏部から固定部に跨るように面外補剛材を設けたので、従来のストレートタイプのダンパーのように降伏部と固定部との境界部に応力集中が生じてそこから破断が生じるようなことを防止することができる。
【００２７】
請求項２の発明は、拘束部材を面外補剛材としての溝形鋼と面内補剛材としての帯鋼をＨ形に組み立てるようにしたので、この拘束部材により芯材の面外座屈および面内座屈を確実に拘束することができるし、ブレースダンパー自体が実質的にＨ形断面となって通常のＨ形鋼からなるダンパーと同様に取り扱うことができる。
【００２８】
請求項３の発明は、固定部に補強部材を取り付けることで芯材の両端部の断面形状を十字形あるいはＨ形としたので、このブレースダンパーを建物に対して通常の形態で簡略かつ確実に接合することができる。
【図面の簡単な説明】
【図１】本発明の第１実施形態であるブレースダンパーの外観を示す図である。
【図２】同、断面図である。
【図３】同、要部斜視図である。
【図４】同、各構成要素を示す図である。
【図５】本発明の第２実施形態であるブレースダンパーの外観を示す図である。
【図６】同、断面図である。
【図７】同、要部斜視図である。
【図８】同、各構成要素を示す図である。
【図９】従来のブレースダンパーの一例を示す図である。
【図１０】従来のストレートタイプのダンパーの一例を示す図である。
【図１１】同、他の例を示す図である。
【符号の説明】
１１芯材
１１ａ降伏部
１１ｂ固定部
１１ｃ円弧部
１２拘束部材
１３補強リブ（補強部材）
１４溝形鋼（面外補剛材）
１４ａウエブ
１４ｂフランジ
１５帯鋼（面内補剛材）
１６ボルト
１７，１８絶縁材
１９縦リブ
２０横リブ
２１スリット
２２綴りボルト
２３ボルト孔
２４フランジ板（補強部材）[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a brace damper that is installed as a brace in a building and also functions as a damper that absorbs vibration energy of the building.
[0002]
[Prior art]
Vibration control structures that control vibration and damage caused by earthquakes by installing vibration control dampers at key points in buildings are becoming common. There are various types of damping dampers applicable to this type of structure, such as steel dampers, friction dampers, viscous dampers, etc.Especially, steel dampers that use the hysteresis energy absorbed by the yielding of steel materials have low damping performance at low cost. The brace-type steel damper is considered to be the most effective because the mechanism is simple, the design is easy to handle, and no installation space is required. ing.
[0003]
As this kind of brace type steel damper, for example, as shown in Patent Literature 1 or Non Patent Literature 1 or Non Patent Literature 2, a structure in which a strip steel plate yielding in an axial direction is used as a core material to restrain buckling from the outside. Stuff has been proposed.
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2002-235380 [Non-Patent Document 1]
Kobayashi and 2 others, "Experiment for confirming the strength of buckling-restrained braces due to weight reduction,"
Summary of the Architectural Institute of Japan Annual Meeting (Hokuriku), August 2002, p. 549-550
[Non-patent document 2]
Nakamura and 5 others, "Fatigue performance of full-scale unbonded brace (part 2: experimental results)", Abstracts of Academic Lecture Meeting of the Architectural Institute of Japan (China), September 1999, p. 815-816
[0005]
As shown in FIG. 9, the brace damper disclosed in Patent Literature 1 has a buckling of a core 1 by attaching a restraining member 2 to the outside of a core 1 having both ends fixed to a building and functioning as a brace. In the structure, the width of the central portion of the core material 1 is reduced to be set as a yield portion 1a, and plastic strain is concentrated on the yield portion 1a to yield. is there.
[0006]
The buckling restrained brace shown in Non-Patent Document 1 is configured to restrain a buckling by mounting a restraining member 4 made of a channel steel or a strip steel on the outside of a core material 3 as shown in FIG. However, the core member 3 is of a straight type having a constant width without providing a yielding portion. In such a straight type, since the plastic strain is dispersed and reduced over the entire length of the core material 3 as compared with the case where the yielded portion is provided, the energy absorption efficiency is slightly lowered, but the fatigue characteristics are excellent. The unbonded brace damper shown in Non-Patent Document 2 is of the same straight type as described above, although the width of both ends of the core material 3 is slightly increased as shown in FIG.
[0007]
[Problems to be solved by the invention]
By the way, the brace damper disclosed in Patent Literature 1 is provided with the yielding portion 1a in the center of the core material 1, so that the plastic strain is concentrated on the yielding portion 1a so that the seismic energy can be effectively absorbed. On the other hand, on the other hand, the width dimension other than the yielding portion 1a has to be larger than the minimum required dimension as a damper, so that it has been somewhat difficult to reduce the overall size and weight.
[0008]
On the other hand, in the straight type shown in Non-Patent Documents 1 and 2, the width can be minimized, which is advantageous in reducing the size and weight. Since the plastic strain is dispersed over the entire length of the material 3, stress concentrates on the boundary between the portion where the buckling is restrained by the restraining member 4 and the portion where the buckling is not restrained. There is a problem that the core material 3 is apt to be broken starting from the position 5a of the tip of the core 5.
[0009]
In view of the above circumstances, an object of the present invention is to provide an effective brace damper that can be sufficiently reduced in size and weight and that can also prevent local breakage.
[0010]
[Means for Solving the Problems]
The invention according to claim 1 is a brace damper that is installed as a brace in a building and also functions as a damper that absorbs vibration energy of the building, wherein both ends are fixed to the building and receive a predetermined axial force. And a restraint member attached to the outside of the core material to restrain its buckling while allowing its axial deformation, and the core material has almost the entire length except for both ends. The fixed width is a fixed part whose width is larger than the yielded part, and the fixed part also serves as a mounting member to the building, and the surface of the fixed part A reinforcing member for increasing the external rigidity is provided, and the restraining member straddles the yielding portion of the core material from the yielding portion to the fixing portion and sandwiches them from both sides so that the yielding portion and the fixing portion have a surface outer seat in the plate thickness direction. Out of the plane that restrains buckling Fastened to both out-of-plane stiffeners on both sides of the yielding portion of the rigid material and the core material to connect the out-of-plane stiffening materials and restrain the yielding portion in-plane buckling in the width direction of the plate And a pair of in-plane stiffeners.
[0011]
According to a second aspect of the present invention, in the brace damper according to the first aspect of the present invention, the out-of-plane stiffener is formed of a channel steel having a web sandwiching a core and flanges integrally formed on both side edges thereof. The stiffener is composed of a pair of steel strips fastened to the flanges of both out-of-plane stiffeners, and the cross-sectional shape of the restraining member is H-shaped by assembling the channel steel and the steel strip. It is characterized by having.
[0012]
According to a third aspect of the present invention, in the brace damper of the first or second aspect of the present invention, the reinforcing member is attached to the fixing portion, so that the cross-sectional shape at both ends of the core member is a cross shape or an H shape. And
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
1 to 4 show a first embodiment of a brace damper of the present invention. This is basically similar to the conventional brace damper shown in FIG. 9, in which both ends are fixed to the building and a core material 11 made of a strip steel plate which yields when subjected to a predetermined axial force; And a restraining member 12 which is attached to the outside of the material 11 and restrains buckling while allowing its axial deformation. However, the configuration of the core member and the restraining member is different from that of the conventional one. I have.
[0014]
That is, as the core material 11 in the brace damper of the present embodiment, a strip steel plate made of low yield point steel or mild steel is adopted, and as shown in FIG. Is a constant yielding portion 11a. Only the both ends fixed to the building are fixed portions 11b whose width dimension is about 1.5 times larger than the yielded portion 11a, and the width at the boundary between the yielded portion 11a and the fixed portion 11b. An arc portion 11c is formed so that the dimension changes smoothly. Reinforcing ribs (reinforcing members) 13 are also attached to both surfaces of the fixing portion 11b by welding so as to also serve as attachment members for fixing the core member 11 to the building and to increase out-of-plane rigidity of the fixing portion 11b. Thereby, as shown in FIG. 2 (b), the cross-sectional shape of both ends of the core material 11 has a cross shape.
[0015]
The restraining member 12 in the brace damper of the present embodiment includes a pair of channel steels 14 as an out-of-plane stiffener for restraining out-of-plane buckling of the core 11 in the thickness direction, and It consists of a pair of strip steels 15 as in-plane stiffeners that restrain in-plane buckling. As shown in FIG. 2 (a), a channel steel 14 as an out-of-plane stiffener is formed integrally with a web 14a having a width slightly larger than the width at the yield portion 11a of the core material 11, and on both side edges thereof. The band steel 15 as an in-plane stiffener is fastened to the flanges 14b of the two channel steels 14 back to back by a large number of bolts 16. By assembling the channel steel 14 and the band steel 15 so as to surround the core material 11, the cross-sectional shape of the restraining member 12 is H-shaped.
[0016]
As shown in FIG. 3, the length of the channel steel 14 is slightly longer than the length of the yield portion 11a of the core material 11, and the length of the channel steel 14 is changed from the yield portion 11a of the core material 11 to the fixing portion 11b. So that not only the yielding portion 11a but also the fixing portion 11b is sandwiched by both ends at the same time. The length of the steel strip 15 is shorter than that of the channel steel 14 in order to avoid interference with the fixing part 11b of the core material 11, and the steel strip 15 has a groove in which only the yield part 11a is sandwiched from above and below. It is fastened to the section steel 14.
[0017]
As described above, the restraining member 12 in which the channel steel 14 and the strip steel 15 are assembled into an H shape and attached to the core 11 restrains the out-of-plane buckling and the in-plane buckling of the core 11. However, in order for the core material 11 to function as a damper, it is necessary that the axial deformation of the core material 11 is not restricted, and therefore, the web 14a of each channel steel 14 and the surface of the core material 11 An insulating material 17 is interposed between them to maintain them in an unbonded (non-adhered) state and allow relative deformation in the axial direction. As the insulating material 17, for example, a sheet material having a thickness of about 1 mm made of a polymer material such as chloroprene rubber or the like can be suitably used, and as shown in FIG. In this case, it may be processed in the same shape as that described above, and may be attached to the web 14a of the channel steel 14 in advance when assembling the restraining member 12. Further, a similar insulating material 18 (see FIG. 4 (a)) is provided on the small face at both ends of the yielded portion 11a of the core material 11 so as to be interposed between the end face of the strip 15 and the inner face. It is good to provide.
[0018]
As shown in FIG. 4 (c), a vertical rib 19 and a horizontal rib 20 as stiffening members for sufficiently increasing the out-of-plane rigidity of the channel steel 14 are welded to the channel steel 14. An out-of-plane stiffening effect on the core material 11 by the channel steel 14 is sufficiently ensured. Slits 21 are formed at both ends of the channel steel 14 and the insulating material 17 to avoid interference with the reinforcing ribs 13 welded to both ends of the core material 11. Further, both ends of the channel steel 14 are connected to the fixing portion 11b of the core material 11 by spelling bolts 22 penetrating them, but the spelling bolts 22 do not restrict the axial deformation of the core material 11. As shown in FIGS. 4 (a) and 4 (b), among the bolt holes 23 for passing the spelling bolts 22, those formed in the fixing portion 11b and the insulating material 17 at one end of the core material 11 are provided. A long hole is formed in the core material 11 in the axial direction, and fastening by the spelling bolt 22 is to be manually tightened without being fully tightened.
[0019]
With the above configuration, the brace damper of the present embodiment can be reduced in size and weight as compared with the conventional brace damper shown in FIG. 9, and the conventional straight type as shown in FIGS. It is less likely to cause local stress concentration and rupture due to the local stress concentration as compared with those of the above, and is extremely effective having both advantages.
[0020]
That is, in the conventional brace damper shown in FIG. 9, the yielding portion 1a is formed only in the central portion of the core material 1 and the width of the other portions is made larger than the yielding portion 1a. Although there is a limit in reducing the weight, in the present embodiment, substantially the entire core material 11 is formed as a yielding portion 11a except for the fixing portions 11b at both ends, and the necessary minimum width dimension is provided over substantially the entire length thereof. can do.
[0021]
Further, not only the core member 11 but also the channel steel 14 as an out-of-plane stiffener in the restraining member 12 can be made the minimum necessary size. Since the deformation is small, the out-of-plane buckling restraining effect of the channel steel 14 on the core material 11 can be naturally improved, and in some cases, the vertical ribs 19 and the horizontal ribs 20 as stiffening members provided on the channel steel 14. Can be omitted or reduced. Further, in the conventional brace damper, since the width dimension of the yielding portion 1a is reduced, the restraining member 2 itself cannot effectively restrain in-plane buckling of the yielding portion 1a in the width direction. When the yielding portion 1a is long, it is necessary to provide some kind of stiffening member between them. However, in the brace damper of the present embodiment, the band steel 15 as the in-plane stiffening material itself is the entire length of the core material 11. Therefore, it is not necessary to provide a special stiffening member. From the above, the brace damper of the present embodiment can be sufficiently reduced in size and weight as compared with the conventional brace damper as shown in FIG. 9, and the configuration can be simplified and simplified. It is also possible to realize low cost.
[0022]
However, by simply fixing the width of the core material 11 and simply attaching the restraint member 12 only to the yielding portion 11a, the restraint can be performed similarly to the conventional straight type shown in FIGS. Stress concentration occurs at the boundary between the constrained portion and the non-constrained portion due to the member 12, and there is a concern that the end of the core material 11 may be broken. Therefore, in the present embodiment, an arc portion 11c is provided at the boundary between the yielding portion 11a and the fixing portion 11b of the core material 11 to make the cross-sectional change there smooth, and the extrapolation forming the restraining member 12 is performed. A channel steel 14 as a rigid material is mounted so as to straddle from the yielding portion 11a to the fixing portion 11b, and the reinforcing ribs 13 provided on the fixing portion 11b of the core material 11 are provided only on the fixing portion 11b, and up to the yielding portion 11a. Thus, stress concentration is prevented from occurring at the boundary between the yielding portion 11a and the fixing portion 11b, thereby preventing breakage there.
[0023]
Of course, the brace damper of the present embodiment can use a strip steel plate or a grooved steel, which is a general-purpose construction material, almost as it is, welding a reinforcing rib 13 to the fixing portion 11b of the core material 11, and forming a groove if necessary. Except for welding the vertical ribs 19 and the horizontal ribs 20 as the out-of-plane stiffeners to the section steel 14, it can be easily and inexpensively assembled by simple bolting, and its appearance is substantially the same as that of the H section steel. Therefore, it can be installed in a building without requiring an extra space like a normal brace or a conventional brace damper.
[0024]
In the first embodiment, the reinforcing ribs 13 are welded one by one to both sides of the fixing portions 11b at both ends of the core material 11 so that the cross-sectional shape there is a simple cross shape. Depending on the situation of the connection, the cross-sectional shape of the end portion of the core material 11 may be changed to another shape, for example, an H shape instead of the cross shape.
[0025]
5 to 8 show a second embodiment in which the cross-sectional shape of the end of the core material 11 is changed to an H shape based on the first embodiment. This is because two flange plates 24 are welded as reinforcing members to the small face of the fixing portion 11b of the core material 11 to form an H-shaped cross section, and accordingly, in the first embodiment, the channel steel 14 is used. The second embodiment is different from the first embodiment in that the slit 21 formed in the first embodiment is omitted and the number of the spelling bolts 22 is one at each end, but other configurations are the same as the first embodiment. belongs to. In the brace damper of the second embodiment, in addition to obtaining basically the same effects as those of the first embodiment, an H-shaped steel is frequently used by making the end of the core material 11 H-shaped. And the number of bolts per one place can be secured by the flange plate 24, so that the length and width of the fixing portion 11b can be reduced and the number of bolt rows can be reduced. There is an advantage. In any case, the cross-sectional shape of the end of the core material 11 may be optimally set in accordance with the structure and form of the joint with the building and other various conditions. It is also possible to form both ends in different shapes such as a shape, and of course it is also possible to adopt a shape other than a cross shape or an H shape.
[0026]
【The invention's effect】
According to the first aspect of the present invention, the width of the core is constant over substantially the entire length except for both ends, so that the core and the restraining member can be reduced to the minimum necessary size. As compared with the brace damper, the size and weight can be reduced sufficiently and the cost can be reduced. In addition, only the both ends of the core material have a large width dimension, a reinforcing member is provided there, and an out-of-plane stiffening material is provided so as to straddle from the yielding part to the fixed part, so like a conventional straight type damper It is possible to prevent stress concentration from occurring at the boundary between the yielded portion and the fixed portion and causing breakage therefrom.
[0027]
According to the second aspect of the present invention, since the groove member as the out-of-plane stiffener and the steel strip as the in-plane stiffener are assembled into an H-shape, the out-of-plane seat of the core material is formed by the restraint member. The buckling and in-plane buckling can be reliably restrained, and the brace damper itself has a substantially H-shaped cross section and can be handled in the same manner as a damper made of a normal H-shaped steel.
[0028]
According to the third aspect of the present invention, since the cross-sectional shape of the both ends of the core material is made to be a cross shape or an H shape by attaching a reinforcing member to the fixing portion, this brace damper can be simply and reliably applied to a building in a normal form. Can be joined.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an appearance of a brace damper according to a first embodiment of the present invention.
FIG. 2 is a sectional view of the same.
FIG. 3 is a perspective view of an essential part of the same.
FIG. 4 is a diagram showing each component.
FIG. 5 is a diagram illustrating an appearance of a brace damper according to a second embodiment of the present invention.
FIG. 6 is a sectional view of the same.
FIG. 7 is a perspective view of the same main part.
FIG. 8 is a diagram showing each component.
FIG. 9 is a diagram showing an example of a conventional brace damper.
FIG. 10 is a view showing an example of a conventional straight type damper.
FIG. 11 is a diagram showing another example of the same.
[Explanation of symbols]
11 Core material 11a Yield part 11b Fixed part 11c Arc part 12 Restriction member 13 Reinforcement rib (reinforcement member)
14 Channel steel (out-of-plane stiffener)
14a Web 14b Flange 15 Strip steel (in-plane stiffener)
16 Bolts 17, 18 Insulating material 19 Vertical ribs 20 Horizontal ribs 21 Slits 22 Spelling bolts 23 Bolt holes 24 Flange plate (reinforcing member)

Claims

A brace damper that is installed as a brace in the building and also functions as a damper that absorbs the vibration energy of the building,
A core made of strip steel that yields when both ends are fixed to the building and receives a predetermined axial force, and a restraint that is attached to the outside of the core and restrains buckling while allowing its axial deformation And a member,
The core material is a yielded portion having a constant width over almost the entire length except for both ends, and only the both ends are fixed portions having a larger width than the yielded portion. Reinforcing members are provided to increase the out-of-plane rigidity of the fixed part while also serving as an attachment member to the
The constraining member is a pair of out-of-plane stiffeners that restrain the out-of-plane buckling of the yielded portion and the fixed portion in the plate thickness direction by sandwiching them from both sides from the yield portion of the core material to the fixing portion. , On both sides of the yielding portion of the core material, the pair of fastening members are connected to the out-of-plane stiffeners to connect the out-of-plane stiffening materials and restrain the yielding portion from buckling in the plane in the width direction of the plate. A brace damper made of an in-plane stiffener.

The out-of-plane stiffener consists of a web sandwiching the core and channel steel with flanges integrally formed on both side edges, and the in-plane stiffener is fastened to the flanges of both out-of-plane stiffeners The brace damper according to claim 1, wherein the cross-sectional shape of the restraining member is H-shaped by assembling the pair of strip steels and assembling the channel steel and the strip steel.

The brace damper according to claim 1 or 2, wherein a cross-sectional shape at both end portions of the core material is formed into a cross shape or an H shape by attaching a reinforcing member to the fixing portion.